Dynamo-electric machine



(No Model.)

F. K. FITCH.

DYNAMO ELECTRIC MACHINE.

No. 285,249. Patented Sept. 18, 1883.

UNITED STATES PATENT OFFICE.

FREDERICK K. FITCH, OF N E\V YORK, N. Y., ASSIGNOR TO THE FITCH ELEC-TRIC LIGHTING AND CONSTRUCTION COMPANY, OF NE YORK.

DYNAMO-ELECTRIC MACHINE.

SPECIFICATION forming part of Letters Patent No. 285,249, datedSeptember 18,'1883.

Application filed Januar) 17, lit-3.

To all? whom it may cancer/L:

Be it known that I, FREDERICK K. Frrcn, of New York, in the county ofNew York and State of New York, have invented certain new and usefulImprovements in Dynamo-Electric Machines; and I do hereby declare thatthe following is a full, clear, and exact description of the invention,which will enable others skilled in the art-to which it appcrtains tomake and use the same, reference being had to the acconr panyingdrawings, which form a part of this specification, in which Figure 1 isan end elemtion with bearings and commutator removed. Fig. 2 is a planview. Figs. 3 and 4. are respectively a face view and edge view of onearmature-ring, showing form and construction. Fig. 5 is a graphicdiagram of the mode of connecting the armature-coils. Fig. 6 is anothermode otcon- 2o nection.

The object of this invention is to facilitate the construction of thearmature of a dynamoelectric machine, to so arrange the armature andfield-magnets that a very intense field of force will be aiforded, andthrough which by my construction a verylarge aggregate of armature-coni'luctor can be passed at right angles to the lines of force,in which the weight of the armature shall be very little compared to thecurrent generated.

To these and other ends my invention consists in the construction,arrangement, and combination of parts, substantially as hereinafterfully described and claimed.

Briefly, one of the chief characteristics of my machine is the armatureand its relation to the fields of force. I construct the armature of anumber of thin iron rings wider radially than thick, mount these atintervals on a central shaft, and revolve them so that each ringrevolves in slots in the pole-pieces of the field magnets. This givesrise to many advantages, as will be seen.

In the drawings, A represents the inducingcoils of the field-magnets,whose cores, solid or sectional, are so produced as to form archedpole-pieces made up of the parallel bars a, having intervening slots, asshown by Fi 2. In the slots thus formed the respective armatureringsrotate and are arranged as follows: The

(No model.)

shaft b is journaled in any suitable manner-in Q the present case in thearched journalbearings C C at the respective ends bolted to thefield-magnets. Upon shaft 1), I place a single long spider, d d, orasmany short spiders as there are rings in the armature. Each of the ringsis in turn fitted upon the shaft by means of the spider d. The ring ismade in two halves, e 0, (see Figs. 3 and 4,) with overlappingjunctions, and bolted or riveted together, as shown. The ring isradially grooved, and in its general form is similar to the \\"ell-knownPacinotti ring, and the radial grooves are each wound similarly withinsulated wire 1' until full, as in Fig. 1, the direction pf windingbeing always the same. The ring 6 e is conveniently fitted to the spiderby forming radial tenonsf on the latter and grooves g on the inner edgeof the ring, as shown by Fig. 1, the ring then being slipped or drivenon the spider. The several rings 0 e e, &c., are spaced apart so thatthey will correspond to and enter the slots in the polepieces a.

In the drawings, Fig. 2, the pole-pieces are each composed of eightparallel bars, u, having seven intervening parallel slots. The armaturetherefore is made up of seven narrow rings, 0 e, &c., all set alike withreference to their coils-4. 6., all the coils numbered 1 are in lineparallel with the shaft, as are all coils numbered 2, and so on.

The collecting-cylinder It is of the usual cylindrical form, having asmany parallel seg ments as there are coils t 011 a ring. The coils ofall the rings are connected up in either of two ways. For currents ofhigh electro-motive force and small volumelprocced as illustrated inFig. 5. The first end of coil 1 on ring 1 is connected to the segment kof the collector, and the last end of the same coil is connected to thefirst end of coil 1 on ring 2, whose last end is likewise connected tothe first end of coil 1 on ring 3,whose last end islikewise connected tothe first end of coil 1 on ring 4, and the last end of the latter isconnected to segmentk' of the collector. The first end ofcoil 2 of ring1 is connected to the same segment, and after seriatim connection of allcoils 2 of the rings the last end isbrought to seg ment k, and so onuntil the last end of the last 100 coil of the last ring is brought tothe first segment, is, of the collecting-cylinder. Twodiametricallyopposite brushes, m m, are suitably mounted to take off thecurrents, which of course will be in a common direction in an externalcircuit. g I

For currents of low electro-motive force and large volume thecouplingwill be as in Fig. 6. The first end .of all the coils No. 1 ofall the from my construction: For a given weight of armature a verygreat length of utilizable eonductor is available. The rings beingseparable into two parts, the winding is extremely easy, and for. thesame reason a defective coil can be unwound and rewound with greatfacility and dispatch without waste of good wire. Room is afforded forfree circulation of air, and the parts will be kept cool. Thearmature-core being divided into separate rings, and each revolving inits own' field-slots, the core of each will be the seat of inducedmagnetism on both sides independently, and the conductor thereon will oneach side rotate in a most powerful field of force and in a very narrowcompass. For machines of different capacities there need not be a greatvariety of sizes as to diameters. since the armature may be prolonged byadding on more rings instead of increasing their diameter. The rings,beingthimwill easily discharge their magnetism and not become highlyheated.

The field-coils A may be coupled in series in the circuit or in aderived circuit, or they may be energized by a separate source ofcurrent.

The slotted form of the field-magnet poles may be secured byconstructing the cores of the field magnets of parallel bars suitablydistanced apart laterally.

I claim as my invention 1. In a dynamoor magneto electric machine,

a rotary armature composed oftwo or more narrow rings, each wound withseparate coils of insulated conductor, said coils being arranged in rowsparallel to the axis, in combination with a collecting-cylinder composedof as many segments as there are coils in one ring,

all the coils in each of said rows being connectedsem'atim or inmultiple arc with their respective ends to two adjoining segments of thecollector, substantially as described. I

2. In a dynamo or magneto electric machine, the combination of anarmature composed of two or more rings, each wound with separate 6ocoils of conductor, and a field-magnet slotted so as to overlap saidrings, substantially as described.

3. The armature-ring composed of two'se'micircular portions, adapted tobe joinedltogether, substantially as described, whereby the two portionscan be wound with wire and afterward joined.

4. The armature-ring composed of the two radially-slotted semicircles ee, having'their 7o ends overlapping and secured by bolts or rivets,substantially as described.

In testimonythat I claim the foregoing as my own I have hereto affixedmy signature in presence of two witnesses.

FREDERICK K. FITCH.

\Vitnesses:

SAML. R. DUMMER, J osEPH T. M RRAY.

